/**********************************************************************
 * Copyright (c) 2010, j. montgomery                                  *
 * All rights reserved.                                               *
 *                                                                    *
 * Redistribution and use in source and binary forms, with or without *
 * modification, are permitted provided that the following conditions *
 * are met:                                                           *
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 *   notice, this list of conditions and the following disclaimer.    *
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 *   notice, this list of conditions and the following disclaimer     *
 *   in the documentation and/or other materials provided with the    *
 *   distribution.                                                    *
 *                                                                    *
 * + Neither the name of j. montgomery's employer nor the names of    *
 *   its contributors may be used to endorse or promote products      *
 *   derived from this software without specific prior written        *
 *   permission.                                                      *
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using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace DnDns.Records
{
    public sealed class AaaaRecord : DnsRecordBase
    {
        private string m_ipAddress;

        internal AaaaRecord(RecordHeader dnsHeader) : base(dnsHeader) { }

        public override void ParseRecord(ref MemoryStream ms)
        {
            // TODO: Test and incorporate BinToHex function below
            m_ipAddress =
                ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" + ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" +
                ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" + ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" +
                ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" + ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" +
                ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2") + ":" + ms.ReadByte().ToString("x2") + ms.ReadByte().ToString("x2");
            _answer = "IPv6 Address: " + m_ipAddress;
        }

        // TODO: converted from VB.NET, test to make sure it works properly
        private static string BinToHex(byte[] data)
        {
            if (data != null)
            {
                StringBuilder sb = new System.Text.StringBuilder(1024);
                for (int i = 0; i < data.Length; i++)
                {
                    sb.Append(data[i].ToString("X2"));
                }
                return sb.ToString();
            }
            else
            {
                return null;
            }
        }
        
        // TODO: converted from VB.NET, test to make sure it works properly
        private static byte[] HexToBin(string s)
        {
            int arraySize = s.Length / 2;
            byte[] bytes = new byte[arraySize - 1];
            int counter = 0;

            for (int i = 0; i < s.Length - 1; i = 2)
            {
                string hexValue = s.Substring(i, 2);

                // Tell convert to interpret the string as a 16 bit hex value
                int intValue = Convert.ToInt32(hexValue, 16);
                // Convert the integer to a byte and store it in the array
                bytes[counter] = Convert.ToByte(intValue);
                counter += 1;
            }
            return bytes;
        }
    }
}
